Method for removing an aborted casting from a continuous-casting machine

ABSTRACT

A method for removing an aborted casting from a continuouscasting machine, in which machine the product is bent from the vertical to the horizontal. The aborted casting is cooled, notched, bent, moved downwardly, and removed. Apparatus is disclosed for restraining the descent of the aborted casting, and for controlling the depth of notches.

United States Patent Hofmann et a1.

METHOD FOR REMOVING AN ABORTED CASTING FROM A CONTINUOUS-CASTING MACHINE Inventors: Gottfried Hofmann, Brentwood Borough; George F. Schwartz, Hampton Township, both of Allegheny County, Pa.

Assignee: United States Steel Corporation Filed: May 25, 1972 Appl. No.: 256,662

Related US. Application Data Division of Ser. No. 71,037, Sept. 10, 1970.

U.S. Cl ..164/70, 164/76 Int. Cl. ..B22d 11/12 Field of Search ..164/69, 70, 76, 82, 263, 274,

[ 1 Mar. 27, 1973 [56] References Cited UNITED STATES PATENTS 3,365,791 1/1968 Olsson ..l64/263 X 3,374,828 3/1968 Menu 3,413,774 12/1968 Oberreich ..72/324 Primary Examiner-Robert D. Baldwin Attarney--Ralph H. Dougherty A method for removing an aborted casting from a continuous-casting machine, in which machine the product is bent from the vertical to the horizontal. The aborted casting is cooled, notched, bent, moved downwardly, and removed. Apparatus is disclosed for restraining the descent of the aborted casting, and for controlling the depth of notches.

ABSTRACT 3 Claims, 4 Drawing Figures PATENIEMARzmn SHEET 2 [IF 3 PATENTEUKARNIQB 3, 722,575

SHEEI 3 [IF 3 METHOD FOR REMOVING AN ABORTEI) CASTING FROM A CONTINUOUS-CASTING MACHINE This is a division, of application Ser. No. 71,037, filed Sept. 10, 1970.

This invention relates to the continuous casting of metals and, more particularly, to a method of removing a cold aborted casting from a curved guide rack and to apparatus for controlling the descent of such casting to prevent damage to any downstream structure.

In continuous casting, it occasionally becomes necessary to terminate casting prior to the completion of the casting cycle. Any product already formed extends downwardly from the mold. In commonly used continuous-casting machines, the product is delivered vertically from the mold through pinch rolls, is bent by bending rolls, follows a curved path through a curved casting guide containing additional guide rolls, and ultimately passes through straightener rolls to be delivered in a horizontal direction. In such a casting machine when a coasting is aborted, the length of which casting is greater than the pass-line distance from the pinch rolls to the straightener rolls, no problem exists as it may be removed while still hot and controlled by such pinch and straightener rolls. However, in the event the casting is aborted prior to its attaining such length, if removal were attempted by activating the pinch rolls, the force of gravity would cause the casting to travel freely without restraint after passing the pinch rolls. Such uncontrolled movement of the casting would damage the equipment downstream from the pinch rolls.

Heretofore it has been the usual practice to cut an aborted casting into convenient lengths with a burning torch and remove each piece. This normally requires dismantling of much equipment to reach the entire length of the casting.

Accordingly, it is the principal object of the invention to provide a method for removing an aborted casting quickly and without requiring the dismantling of any equipment or machinery.

It is another object to provide means for controlling the rate of travel of an aborted casting through a casting guide.

It is also an object to provide means for controlling uniformity of notches in the casting.

We have invented a method of removing an aborted casting by notching one edge of the casting at intervals, bending the casting at each notch, restraining the descent of the notched casting by a brake assembly, and removing the casting by means such as an overhead crane.

In the drawings:

FIG. 1 is a side elevational view ofa portion of a continuous-casting machine.

FIG. 2 is a side elevational view of the bending roll assembly on a larger scale than in FIG. 1.

FIG. 3 is a side elevational view of a brake assembly, with the brake shown in dot-dash outline.

FIG. 4 is a side view of the brake assembly taken along line IVIV of FIG. 3.

As shown in FIG. 1 a continuously cast product is delivered vertically from a continuous-casting mold, not shown, and moves downwardly through pinch rolls 12 and 13, by which such downward movement is controlled. Casting 10 passes through and is bent by bending roll assembly 14 having a bending roll 16 extending downwardly therefrom and attached thereto by pivoted arm 17. A chute 19 is located in the vertical path of the casting and serves to assist the entry of casting 10 into casting guide 20, which guide 20 comprises alternate guide rollers and guide chutes. As the casting 10 leaves the last roller of casting guide 20, it enters a roller straightener 22 wherein it is straightened and wherefrom it is delivered horizontally.

When casting must be interrupted prior to the leading end of the casting reaching the straightener, we allow the casting to cool, after which we notch the casting at regular intervals with a cutting torch. Elongated slot 24, in the side plate of bending roll assembly 14, provides access for an oxyacetylene torch to the casting, the bottom of the slot providing a sliding support and guide means for a torch nozzle. We cut the notch as deeply as possible without causing the casting to break when it is subsequently bent. An adjustable stop 25, shown in FIG. 2, controls the notch depth and assures uniformity of depth of each notch. The stop is a metal block, having two flanges 26a and 26b, each flange having an elongated slot 27 therein. Cap screws 28 hold the stop tightly in the desired position. After each notch is cut into the casting, we actuate bending roll 16 to bend the casting. We move the casting downwardly and cut another notch. When the casting extends a sufficient length beyond the bending roll assembly that the leading end has already passed the first roll 29 in the casting guide 20, it may be unnecessary to actuate bending roll 16 after cutting each notch to effect bending of the casting. The casting will bend as a result of the pinch rollsforcing it downward against the rolls in casting guide 20.

By cutting notches at closer intervals, it is possible to bend the casting without actuating bending roll 16. We leave the bending roll in the bending position and bend the casting as the pinch rolls force it downward against the bending roll.

Although the casting is shown in the drawings as notched on the outer edge, it is equally satisfactory to cut the notches in the inner edge.

We prevent the casting from descending uncontrollably with catastrophic results by contacting the surface of the casting with a brake assembly 30, which is located midway between the lowermost pinch roll 13 and straightener 22. The casting may be removed by an overhead crane 31 prior to entry of the casting into the straightener. The casting may be burned into convenient lengths for ease in handling. However, if it is desired to remove the casting after passing through the straightener, straightener roll 32 is moved to upper position 33 which opens the straightener sufficiently to allow a curved casting to pass therethrough. The casting is then removed by an overhead crane as it exits from the straightener.

The brake assembly which we use to restrain the casting includes a braking roll 34 and a cooperating freely rotatable idler roll 35. The braking roll 34 is mounted beneath the passline of the casting and normally rotates freely and acts as a guide and support roll for the casting. Frame 36, which provides support for the entire brake assembly, is fixed to the supporting structure of casting guide 20. Braking roll 34 is journaled in anti-friction bearings 37. A braking means 38 is connected to the roll shaft. A suitable braking means is a caliper disc brake, for example, Model HB-3 manufactured by Fawick Airflex Division of Fawick Corporation, Cleveland, Ohio. Top roll 35 is identical to bottom roll 34. It is journaled in anti-friction bearings 39 mounted on swivel arm 40, which swivel arm 40 is pivotally mounted by pin 41 in frame 36. Both rolls 34 and 35 are internally water cooled. A compression spring assembly 42 is mounted on a hydraulic or air cylinder 43 which, in turn, is mounted in housings 44 atop frame 36 by a trunnion 45. Cylinder 43 has a piston 46 with a rod 47 extending through both ends of the cylinder. The lower end of rod 47 has an eye 48 which is rotatably mounted by pin 49 in housing 50, which housing 50 is fixed atop swivel arm 40. The upper end of rod 47, which extends through compression spring assembly 42, is threaded and fitted with a nut 51 for adjusting spring force. lam nut 52 locks nut 51 into position against the end of compression spring assembly 42. The assembly is covered by protective telescoping sleeves 53 and 54.

- In operation, spring assembly 42 holds top roll 35 in the withdrawn or upper position. When we desire to move the top roll downwardly to force an aborted casting against lower roll 34, we actuate hydraulic cylinder 43 compressing the springs in assembly 42 and forcing the roll downward. Brake 38, acting on lower roll 34, restrains movement of the casting.

To raise roll 35, we remove hydraulic pressure from cylinder 43 allowing spring assembly 42 to return to its original position, retracting swivel arm 40, raising the roll.

Alternatively, roll 35 may be a replaceable block of any desired configuration, and the braking means may be omitted from roll 34. Frictional force would be exerted on the casting by actuating hydraulic cylinder 43 to force the block downward to restrain the uncontrolled descent of the casting.

It can readily be seen from the foregoing that we have invented a method for removing an aborted casting from a continuous-casting machine which does not require dismantling any machinery and will prevent damage to machinery and equipment.

We claim:

1. A method for removing a cooled aborted casting from a substantially vertical continuous-casting machine having a curved guide rack comprising notching the casting above said rack to form notches on one side of said casting at regular intervals, bending the notched casting at each notch to conform to the curve of said rack, restraining the descent of the notched casting through said rack, and removing the notched casting from the bottom of the machine.

2. A method as defined in claim 1 in which descent of the notched casting is restrained by contacting the casting with a brake assembly.

3. A method as defined in claim 1 in which the casting is notched by cutting the casting with a cutting torch. 

1. A method for removing a cooled aborted casting from a substantially vertical continuous-casting machine having a curved guide rack comprising notching the casting above said rack to form notches on one side of said casting at regular intervals, bending the notched casting at each notch to conform to the curve of said rack, restraining the descent of the notched casting through said rack, and removing the notched casting from the bottom of the machine.
 2. A method as defined in claim 1 in which descent of the notched casting is restrained by contacting the casting with a brake assembly.
 3. A method as defined in claim 1 in which the casting is notched by cutting the casting with a cutting torch. 